obligation of restitution; duty to return
Legal or formal term for the obligation to return something to its original owner or state, often used in contexts like international law, property, or funds.
Under the treaty, an obligation to return the occupied territory arises.
There is an obligation to return improperly received subsidies.
返還 is the act of returning/restoring; 返還義務 is the legal or moral duty to do so.
義務 is a general duty or obligation; 返還義務 specifies the duty to return/restore.
Compound of 返還 (return, restoration) and 義務 (duty, obligation).